where \(a=\lbrace \tilde{m}_1, \tilde{m}_2,\cdots , \tilde{m}_{L}\rbrace \) ,
\(b=\left\lbrace  \frac{ \tilde{d}_1^{-\tilde{\xi }_1} \sigma _{\tilde{h}_1}^2 \sigma _{\tilde{s}_1}^2}{2 \tilde{m}_1}, \frac{\tilde{d}_2^{-\tilde{\xi }_2} \sigma _{\tilde{h}_2}^2 \sigma _{\tilde{s}_2}^2}{2 \tilde{m}_2}, \cdots , \frac{\tilde{d}_L^{-\tilde{\xi }_L} \sigma _{\tilde{h}_L}^2 \sigma _{\tilde{s}_L}^2}{2 \tilde{m}_L} \right\rbrace \) , and \(c=\frac{\sigma _w^2}{2}\) . Furthermore, \(\tilde{d}_i\)  and \(\tilde{\xi }_i\) , represent the distance and the corresponding link path-loss exponent between the \(i-\) th active PU and the ED, whereas \(\sigma _{\tilde{s}_i}^2\) , and \(\sigma _{\tilde{h}_i}^2\)  stand for the variances of the \(i-\) th active PU's transmitted signal and \(i-\) th fading channel.
The shape factor of the fading channel between the \(i-\) th active PU and the CR device is denoted as \(\tilde{m}_i\) .
Moreover, note that in (REF ), \(\Xi (i,k)\)  is defined in [1]}
Note that there is a typo in [1]}. The correct expression is
\(\Xi (i,a_i - k) \hspace{-1.42271pt}=\hspace{-1.42271pt} \frac{1}{k}\hspace{-2.84544pt} \sum _{\begin{array}{c}q=1\\q\ne i\end{array}}^{L} \sum _{j=1}^{k} \frac{a_q}{b_{i}^j}\left(\frac{1}{b_i} - \frac{1}{b_q}\right)^{-j} \Xi (i,a_i-k+j).\) 
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